JPH0383688A - Thermal transfer recording material - Google Patents

Abstract

PURPOSE:To obtain a color image having good gradation and excellent in fixing properties by laminating a thermal layer compounded with a dye compound represented by a specific general formula to a support to form a thermal transfer recording material. CONSTITUTION:A dye represented by formula I (wherein R<1> is H, a halogen atom, an alkyl group or an aryl group, R<2> is a cycloalkyl group, an acylamino group or a cyano group, R<3> is an aryl group or an alkenyl group and n is an integer of 1 - 4) is dissolved in a solvent along with a binder such as a polyacrylic acid type water-soluble polymer to prepare dye compound-containing ink. This ink is applied to a support such as a heat-resistant plastic film and dried to form a thermal layer to obtain a thermal transfer recording material. The use amount of the dye compound is pref. about 0.1 - 20g per 1m<2> of the support.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a thermal transfer material, and more particularly to a novel thermal transfer material containing a magenta dye with excellent spectral properties, heat resistance, and fixing properties, and an image forming method using the dye. . [Background of the Invention] Color recording techniques such as inkjet, electrophotography, and thermal transfer are being considered as methods for obtaining color hard copies. Among these, the thermal transfer method in particular has advantages such as ease of operation and maintenance, miniaturization and cost reduction of the device, and low running costs. In this thermal transfer method, a transfer sheet (also called a heat-sensitive transfer material) having a meltable ink layer on a support is heated by a thermal head, and the ink is transferred onto a transfer sheet (also called an image-receiving material). A thermal diffusion method in which a transfer sheet having an ink layer containing a heat-diffusible dye (sublimable dye) is heated by a thermal head to transfer the heat-diffusible dye to a transfer sheet. There are two types of transfer methods (sublimation transfer method), but this thermal diffusion transfer method controls the gradation of the image by changing the amount of dye transferred in response to changes in the thermal energy of the thermal head. This is advantageous for full-color recording. By the way, in thermal transfer recording using the thermal diffusion transfer method,
The dye used in thermal transfer materials is important, and has a major impact on transfer recording speed, image quality, image storage stability, etc. Therefore, the dye used in the thermal diffusion transfer method described above must have the following properties. (1) Easy thermal diffusion (sublimation) under thermal recording conditions (head temperature, head heating time). (2) It has a hue favorable for color reproduction. (3) Do not thermally decompose at the heating temperature during recording. (4) Good light resistance, heat resistance, moisture resistance, chemical resistance, etc. (5) It has a large molar extinction coefficient. (6) Easily added to thermal transfer materials. (7) Easy to synthesize. Furthermore, in addition to this, excellent image fixing properties are required. Conventionally, as a magenta dye for thermal transfer materials, JP-A-5
No. 9-78896, No. 60-30392, No. 60-3
No. 0394, No. 60-253595, No. 61-262
No. 190, No. 63-5992, No. 63-205288
No., No. 64-1591, No. 64-63194, etc. disclose anthraquinone dyes, azo dyes, azomethine dyes, etc., but in particular, thermal diffusivity, hue, heat resistance, light resistance, etc. A dye that satisfies the above requirements and has good fixing properties has not yet been found. Therefore, from the above-mentioned viewpoint, the present inventors continued various studies on dyes for thermal transfer materials and image forming methods using the same, and as a result, unexpectedly, the dye of general formula [I] was found. The present invention has been completed based on the discovery that it satisfies the conditions and has particularly excellent fixing properties. [Objective of the Invention] Therefore, the object of the present invention is to provide a photosensitive material using a magenta dye that satisfies the above-mentioned properties and characteristics (thermal diffusivity, hue, heat resistance, light resistance, etc.) and has significantly improved fixing properties. It is an object of the present invention to provide a thermal transfer material and an image forming method using the dye. [Structure of the Invention] The object of the present invention is to: 1) provide a thermal transfer material containing at least a dye compound represented by the general formula [I] on a support; Thermal transfer recording material characterized by having a layer and general formula [I] [wherein R1 is a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkenyl group, an aralkyl group, an alkoxy group, Aryloxy group, cyano group, acylamino group, alkylthio group, arylthio group,
Represents a sulfonyl group, a ureido group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, an acyl group, and an ayono group. R2 is an alkyl group, a cycloalkyl group, an aryl group,
Represents an acylamino group, an alkylatorano group, a sulfonylamino group, an alkoxycarbonyl group, a ureido group, or a cyano group. R3 represents an aryl group, an alkyl group 1, a cycloalkyl group, an alkenyl group, an aralkyl group, or a heterocyclic residue. n represents 1, 2.3 or 4. n is 2.3 or 4
, R1 may be the same or different, and furthermore, these substituents may be bonded to each other to form a carbocycle or a heterocycle.] 2) At least the general formula [
A heat-sensitive transfer material having a heat-sensitive layer containing a dye compound represented by I] is heated from the back side of the support according to the image information, and the dye compound is applied to the image-receiving material in the presence of a basic compound and/or mordant. It is distantly related to the thermal transfer image forming method, which is characterized by forming an image. The present invention will be explained in more detail below. - In formula [I], R1 is a hydrogen atom, a halogen atom (e.g. chlorine atom, fluorine atom, etc.), an alkyl group (e.g. methyl group, ethyl group, isopropyl group, n-butyl group), a cycloalkyl group (e.g. cyclopentyl group) , cyclohexyl group, etc.), aryl group (e.g. phenyl group, etc.)
, alkenyl group (e.g. 2-propenyl group, etc.), aralkyl group (e.g. benzyl group, 2-phenethyl group, etc.), alkoxy group (e.g. methoxy group, ethoxy group, isopropoxy group, n-butoxy group, etc.), aryloxy group (e.g., phenoxy group, etc.), cyano group, acylamino group (e.g., acetylamino group, propionyl group, etc.), alkylthio group (e.g., methylthio group, ethylthio group, n
-butylthio group, etc.), arylthio group (e.g. phenylthio group), sulfonylamino group (e.g. methanesulfonylamino group, benzenesulfonylamino group, etc.), ureido group (e.g. 3-methylureido group, 3,3-dimethylureido group) , 1,3-dimethylureido group, etc.), carbamoyl group (e.g., methylcarbamoyl group, ethylcarbamoyl group, dimethylcarbamoyl group, etc.), sulfamoyl group (e.g., ethylsulfamoyl group, dimethylsulfamoyl group, etc.), alkoxycarbonyl group (e.g. methoxycarbonyl group, ethoxycarbonyl group, etc.), aryloxycarbonyl group (e.g. phenoxycarbonyl group, etc.), sulfonyl group (e.g. methanesulfonyl group, butanesulfonyl group, phenylsulfonyl group, etc.), acyl group (e.g. acetyl group, propanoyl group, etc.) group, butyroyl group, etc.), amino group (mainly methylamino group, ethylamino group, dimethylamino group, etc.). R2 is an alkyl group (e.g. methyl group, ethyl group, etc.),
cycloalkyl group (e.g. cyclopentyl group, etc.), aryl group (e.g. phenyl group, etc.), acylamino group (e.g. acetylamino group, isobutyroyl group, etc.), alkyl group

[No group (e.g. ethylamino group, dimethylamino group)
) groups, etc.), aryla-based groups (e.g., phenyla groups, etc.), sulfonyla-based groups (e.g., methanesulfonylamino groups, benzenesulfonylamino groups, etc.), alkoxycarbonyl groups (e.g., methoxycarbonyl groups, etc.), It represents a ureido group (for example, 3-methylureido, 3,3-dimethylureido, etc.) or a cyano group, and particularly preferably an acylamino group or an arylamino group. R3 represents an aryl group (e.g., phenyl group, etc.), an alkyl group (e.g., methyl group, ethyl group, etc.), a cycloalkyl group (e.g., cyclopentyl group, etc.), an alkenyl group (e.g., 2-propenyl group, etc.), an aralkyl group (e.g., benzyl group, etc.). group, 2-phenethyl group, etc.) or a heterocyclic residue (e.g., pyridyl group, etc.). These R11t 2 R3 may be further substituted, and examples of the substituent include an alkyl group (for example, a methyl group, an ethyl group, a trifluoromethyl group, etc.), an aryl group (for example, a phenyl group, etc.), an alkoxy group ( (e.g. methoxy group, ethoxy group, etc.), amino group (e.g. methyla group)
group, ethylamino group, etc.), azilamino group (e.g., acetyl group, etc.), sulfonyl group (e.g., methanesulfonyl group, etc.), alkoxycarbonyl group (e.g., methoxycarbonyl group), cyano group, nitro group, halogen atom (e.g., chlorine group, etc.). atoms, fluorine atoms, etc.). Further, the group represented by RI R2R3 (including substituents when having a substituent) preferably has 12 or less carbon atoms (particularly preferably 8 or less). The compound represented by the general formula [I] (hereinafter referred to as the compound used in the present invention) is usually the following general formula [I! ] is obtained by oxidative coupling of the coupler represented by the formula and a p-aminophenol derivative. Conventionally known compounds are obtained by oxidative coupling C with p-phenylenediamine derivatives, whereas the compounds used in the present invention are obtained by oxidative coupling with p-aminophenol derivatives,
Therefore, by having a phenolic hydroxyl group, fixing properties are improved. Next, typical compound examples of the dye represented by the general formula [I1 used in the present invention are shown, but the present invention is not limited thereto. The compound used in the present invention gives a good magenta hue under basic conditions, but under acidic conditions it shifts to a pale color and takes on a red to orange hue. Therefore, although it is possible to form an image by transferring the compound used in the present invention alone, a clear magenta image can be obtained by forming an image in the presence of a basic compound in the image-receiving layer. Furthermore, the compound used in the present invention gives a good cyan hue when used in a mordant, regardless of the presence or absence of a basic compound. Therefore, it is preferable to form an image in the presence of a basic compound (or alkaline agent) and/or mordant in the image-receiving layer. In particular, a method of forming an image in the presence of a mordant is more preferable because the dye is mordanted with the mordant, thereby improving fixing properties. In the present invention, the basic compound and/or mordant are added to the image-receiving material (usually referred to as the image-receiving layer), but when the heat-sensitive transfer material has a two-layer structure as described below, the basic compound and/or mordant are added to the heat-fusible layer. Also, a basic compound may be added to the ink layer. In those cases, it is not necessary to necessarily include a basic compound and/or a mordant in the image-receiving layer. As the basic compound used in the present invention, Although there are no particular limitations, inorganic or organic basic compounds are used, such as calcium carbonate, sodium carbonate, sodium acetate,
Examples include Alkirua-kun and Arirua-kun. In the present invention, it is preferable to use a mordant, and it is particularly preferable to add a mordant to the image-receiving layer. The mordants used in the present invention include compounds having a tertiary a) group, compounds having a nitrogen-containing heterocyclic group, and compounds having these 4wjL cation groups. When a mordant is used in the image-receiving layer, it is preferable that the mordant is immobilized, and a polymer mordant is particularly preferred. When the mordant is added to the heat-melting layer of the thermal transfer material, a mordant with a molecular weight of 400 or less is preferable. preferable. The polymer mordant may constitute the image-receiving layer by itself, but it is usually used together with another suitable binder that constitutes the image-receiving layer. The binder has a glass transition point of 4 as described in JP-A No. 57-207250.
Examples include those formed of heat-resistant organic polymeric substances having a temperature of 0° C. or more and 250° C. or less. These polymers are usually supported on a support as an image-receiving layer, but they may also serve as a support themselves.
rup, E, H, Immergut4i) John
Published by W11ey & 5ons (Synthetic polymers with a listed glass transition point of 40°C or higher are also useful. As polymer mordants, Japanese Patent Application Laid-open Nos. 48-28325, 54-74430, 54-124726, and 55)
-22766, 55-142339, 55-2
No. 3850, No. 60-23851, No. 60-2385
No. 2, No. 60-23853, No. 60-57836,
No. 60-60643, No. 60-118834, No. 6
No. 0-122940, No. 60-122941, No. 60
-122942, US Pat. No. 60-235134, US Pat. No. 2,484,430, US Pat. No. 2,548°564, US Pat.
, No. 309,690, No. 3゜756.814, No. 3,
No. 898,088, No. 3.958,995, No. 4.1
No. 15,124, No. 4,124,386, No. 4,19
No. 3,800, No. 4,273,853, No. 4,282
．． No. 305, No. 4,450,224, British Patent No. 1,
No. 594,961, No. 2,056,101, No. 2,0
For example, the following polymer mordants can be used, although they may be selected from those described in various specifications such as No. 93,041. First, examples of the polymer mordant having a tertiary amino group include the following polymers. Hereinafter, specific representative examples of the mordant used in the present invention will be listed, but the present invention is not limited to these examples. (Numbers represent mol%) -1 C)! ! -2 -3 -4 As the nitrogen-containing heterocyclic group, an imidazole group and a pyridyl group are preferable, and the following polymers are exemplified as specific examples of the polymer mordant having a grid. -5 -6- 7- -9 -10 -11 P-12 P-13 -14 -15 Specific examples of the polymer mordant having a quaternary ammonium group include the following polymers. -16 COx N'' CII l- -17 C83N'''-CO2 1- -18 -19 zHs -20 -21 H3 P-22 P-23 l- The thermal transfer material of the present invention contains the dye in a solvent together with a binder. An ink layer or a heat-sensitive layer is obtained by preparing an ink containing a pigment by dissolving it in or dispersing it in the form of fine particles, and coating the ink on a support and drying it. The amount of the dye used in the present invention is preferably 0.1 to 20 g per m2 of support. The image forming method using the heat-sensitive transfer material obtained in this way involves preparing the image-receiving material, aligning the heat-sensitive layer and the image-receiving layer surface, and then applying heat from the back side of the support of the heat-sensitive transfer material according to the image information. When applied, the dye corresponding to this thermal image diffuses into the image-receiving layer, where the dye is fixed and a dye image is obtained. The binder includes water-soluble polymers such as cellulose, polyacrylic acid, polyvinyl alcohol, and polyvinylpyrrolidone; organic solvent-soluble polymers such as acrylic resin, methacrylic resin, polystyrene, polycarbonate, polysulfone, polyethersulfone, and ethyl cellulose; There are polymers. When using a polymer soluble in an organic solvent, it may be used not only by being dissolved in the organic solvent, but also in the form of a latex dispersion. The amount of binder used is 0.1g per 11 supports.
~50g is preferred. The support used in the present invention may be any material as long as it has good dimensional stability and can withstand the heat during recording with a thermal head, including thin paper such as condenser paper, Krashin paper, polyethylene terephthalate, and polyamide. Alternatively, a heat-resistant plastic film such as polycarbonate can be used. The thickness of the support is preferably 2 to 30 μm, and the support has a lower layer for the purpose of improving adhesion with the binder and preventing color transfer to the support and dyeing. Good too. Furthermore, a ripping layer may be provided on the back side of the support (the side opposite to the ink layer) for the purpose of preventing the head from adhering to the support. The ink layer, ie, the heat-sensitive layer, used in the present invention is coated on the support or printed on the support by a side-to-side method such as a gravure method. The thickness of the heat sensitive layer is 0.1μ in dry film thickness.
m to 5 μm is preferable. Solvents for preparing the ink for the heat-sensitive layer include water, alcohols (e.g. ethanol, propatool), cellosolves (e.g. ethyl acetate), aromatics (e.g. toluene, xylene, chlorobenzene), ketones (e.g. acetone, methyl ethyl ketone>, ethers (e.g., tetrahydrofuran, dioxane), chlorinated solvents (e.g., chloroform, trichlorethylene), etc. The heat-sensitive transfer material of the present invention is basically a material that can be used in the present invention on a support. an ink layer consisting of a pigment and a binder;
That is, it is composed of a heat-sensitive layer, but may have a heat-fusible layer containing a heat-fusible compound as described in JP-A-59-106997 on the ink layer. Furthermore, when the thermal transfer material of the present invention is applied to full-color image recording, a cyan ink layer containing a cyan dye, a magenta ink layer containing a heat-diffusible magenta dye, and a heat-diffusible yellow dye are formed on the support. It is preferable that three yellow ink layers are sequentially and repeatedly applied. Further, in addition to the yellow, magenta, and cyan layers, an ink layer containing a black image-forming substance may be further applied as necessary, so that a total of four layers may be repeatedly applied in sequence. [Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.
7 The present invention is not limited only to these examples. Example 1 [Ink layer (heat-sensitive layer)] A mixture having the following composition was treated with a paint conditioner to obtain a uniform solution ink containing a heat-diffusible pigment used in the present invention. Pigment compound Dye -210 g Polyvinyl butyral resin 15 g Methyl ethyl ketone 150 tsfl Toluene 150 mp [Preparation of transfer sheet] The ink containing the above thermally diffusible dye was coated in a 15 μm thick layer.
On a support made of a polyamide film, coated using a wire bar so that the coating amount after drying is 1.0 g per mouth, and dried to form a layer containing a heat-diffusible dye,
A thermal transfer material-1 was produced. Similarly, in place of Dye-2 of thermal transfer material-1,
Thermal transfer materials-2 to 7 were prepared in the same manner as the thermal transfer material-1 except that the dyes shown in Table 2 were used. [Preparation of image-receiving material] 10 g of polyvinylpyrrolidone was dissolved in 100g of a latex dispersion containing 10% polymer mordant (P-16), and the amount of polyvinylpyrrolidone (binder) applied was 10g per 1 m of support. An image-receiving material-A was prepared by coating it on baryta paper. Similarly, image-receiving materials-B to G having the compositions shown in Table 1 were prepared.Table [Thermal transfer image forming method] Layer the thermal transfer sheets (1 to 7) and image receiving materials (A and E) so that the ink-coated surface of the thermal transfer sheet and the image receiving surface of the image receiving material face each other, and apply the thermal head to the thermal transfer sheet from the back side. Image recording was performed. As a result, an image with excellent gradation was obtained. The maximum density of the obtained image is shown in Table 2. The recording conditions at this time were as follows: Main scanning, Linear density of sub-scanning: 4 dots/mm Recording power
Heating time of 0.8W/dot thermal head 20 m5ec (applied energy approx. 11.2x 1O
-3J) to 2 m5ec (applied energy approximately 1.1
The heating time was adjusted stepwise between 2 x 10-'J). Dye- (A) Dye- (B) As is clear from Table 2, a high-density thermal transfer image can be obtained by using the method of the present invention. Example 2 The images obtained in Example 1 (No. 1 to No. 14) were laminated with high-quality dry electrophotographic paper on the image-receiving layer side and contained dioctyl phthalate (30%) as a plasticizer. Regarding the two types, one made of overlapping polyvinyl chloride sheets,
After applying a pressure of 30 g/cm" from above and leaving it at a temperature of 60°C for 3 days, the high-quality paper was peeled off from the image-receiving material and the image density retransferred onto the high-quality paper was measured. Obtained Results are shown in Table 3. As is clear from Table 3, images with excellent fixability can be obtained by the method of the present invention. Example 3 Thermal transfer material and image receiving material A- produced in Example 1 Thermal transfer recording was carried out in the same manner as in Example 1 using G. The density and hue of the obtained images are shown in Table 4. retransferability)
A test was conducted. The results are also shown in Table 4. As is clear from Table 4, the method of the present invention provides images with high density, good hue, and excellent fixing properties. The effect is remarkable. [Effects of the Invention] By the thermal transfer image forming method of the present invention, color images with good gradation and excellent fixing properties can be obtained.

Claims (1)

[Scope of Claims] 1) A heat-sensitive transfer recording material comprising a heat-sensitive layer containing at least a dye compound represented by the general formula [I] on a support. General formula [I] ▲ Numerical formulas, chemical formulas, tables, etc. Oxy group, cyano group, acylamino group, alkylthio group, arylthio group, sulfonylamino group, ureido group, carbamoyl group,
Represents a sulfamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfonyl group, an acyl group, and an amino group. R^2 represents an alkyl group, a cycloalkyl group, an aryl group, an acylamino group, an alkylamino group, a sulfonylamino group, an alkoxycarbonyl group, a ureido group, or a cyano group. R^3 represents an aryl group, an alkyl group, a cycloalkyl group, an alkenyl group, an aralkyl group, or a heterocyclic residue. n represents 1, 2, 3 or 4. n is 2, 3 or 4
In this case, R^1 may be the same or different, and furthermore, these substituents may be bonded to each other to form a carbocycle or a heterocycle. ] 2) A heat-sensitive transfer material having a heat-sensitive layer containing at least a dye compound represented by the general formula [I] on a support is heated from the back side of the support in accordance with image information, and a basic compound and a basic compound are coated on the image-receiving material. A thermal transfer image forming method comprising forming an image using the dye compound in the presence of/or a mordant.